Genetic analysis of human and animal populations has been to study the genetic health and disease susceptibility of several species. A molecular phylogeny of the great and lesser apes and man was derived based on genetic distance of 383 different proteins resolved by 2-dimensional gel electrophoresis. A molecular phylogeny of 37 species of the Felidae family was constructed based on several molecular measures of evolutionary distance. Similarly, consensus phylogenies of the Ursidae (the giant panda, Ailuropoda, and the lesser panda, Ailurus) and the Canidae were derived from distance matrices derived from three distinct molecular measures of genetic distance. A correlative relationship was observed between the extent of genetic variation and the physiology of reproduction during studies of two subspecies of lions. Genetic variation and phylogenetic relationships of Mustela species were examined. A comparative analysis of cytological linkage maps of mammals has indicated a noncontinuous tempo of chromosomal evolution in certain lineages (e.g., primates, felids) that are highly conserved in their chromosomal presentation, while others (rodents, lesser apes, canids) are chromosomally shuffled as if rapid saltatory cytological rearrangements occurred during the speciation events. A reconstruction of cytological rearrangement which had occurred during carnivore evolution has been achieved.